@@ -38,6 +38,19 @@ EXPORT_SYMBOL(pci_pci_problems);
unsigned int pci_pm_d3_delay;
+static void pci_pme_list_scan(struct work_struct *work);
+
+static LIST_HEAD(pci_pme_list);
+static DEFINE_MUTEX(pci_pme_list_mutex);
+static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
+
+struct pci_pme_device {
+ struct list_head list;
+ struct pci_dev *dev;
+};
+
+#define PME_TIMEOUT 1000 /* How long between PME checks */
+
static void pci_dev_d3_sleep(struct pci_dev *dev)
{
unsigned int delay = dev->d3_delay;
@@ -1331,6 +1344,32 @@ bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
return !!(dev->pme_support & (1 << state));
}
+static void pci_pme_list_scan(struct work_struct *work)
+{
+ struct pci_pme_device *pme_dev;
+
+ mutex_lock(&pci_pme_list_mutex);
+ if (!list_empty(&pci_pme_list)) {
+ list_for_each_entry(pme_dev, &pci_pme_list, list)
+ pci_pme_wakeup(pme_dev->dev, NULL);
+ schedule_delayed_work(&pci_pme_work, msecs_to_jiffies(PME_TIMEOUT));
+ }
+ mutex_unlock(&pci_pme_list_mutex);
+}
+
+/**
+ * pci_external_pme - is a device an external PCI PME source?
+ * @dev: PCI device to check
+ *
+ */
+
+static bool pci_external_pme(struct pci_dev *dev)
+{
+ if (pci_is_pcie(dev) || dev->bus->number == 0)
+ return false;
+ return true;
+}
+
/**
* pci_pme_active - enable or disable PCI device's PME# function
* @dev: PCI device to handle.
@@ -1354,6 +1393,44 @@ void pci_pme_active(struct pci_dev *dev, bool enable)
pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
+ /* PCI (as opposed to PCIe) PME requires that the device have
+ its PME# line hooked up correctly. Not all hardware vendors
+ do this, so the PME never gets delivered and the device
+ remains asleep. The easiest way around this is to
+ periodically walk the list of suspended devices and check
+ whether any have their PME flag set. The assumption is that
+ we'll wake up often enough anyway that this won't be a huge
+ hit, and the power savings from the devices will still be a
+ win. */
+
+ if (pci_external_pme(dev)) {
+ struct pci_pme_device *pme_dev;
+ if (enable) {
+ pme_dev = kmalloc(sizeof(struct pci_pme_device),
+ GFP_KERNEL);
+ if (!pme_dev)
+ goto out;
+ pme_dev->dev = dev;
+ mutex_lock(&pci_pme_list_mutex);
+ list_add(&pme_dev->list, &pci_pme_list);
+ if (list_is_singular(&pci_pme_list))
+ schedule_delayed_work(&pci_pme_work,
+ msecs_to_jiffies(PME_TIMEOUT));
+ mutex_unlock(&pci_pme_list_mutex);
+ } else {
+ mutex_lock(&pci_pme_list_mutex);
+ list_for_each_entry(pme_dev, &pci_pme_list, list) {
+ if (pme_dev->dev == dev) {
+ list_del(&pme_dev->list);
+ kfree(pme_dev);
+ break;
+ }
+ }
+ mutex_unlock(&pci_pme_list_mutex);
+ }
+ }
+
+out:
dev_printk(KERN_DEBUG, &dev->dev, "PME# %s\n",
enable ? "enabled" : "disabled");
}